37. You observe the lower limb of the Sun at a sextant altitude (hs) of 41°29.8' on 11 January. The index error is 2.4' off the arc. The height of eye is 68 feet. What is the observed altitude (Ho)?

The observed altitude is calculated by adding the index correction (2.4' since it's off the arc), subtracting the dip correction (-8.0' for a 68-foot height of eye), and adding the Sun's lower limb main correction (+15.2' from the Nautical Almanac), resulting in an observed altitude of 4139.4'.